NO. 1158. 



FRESH-WATER CRABS OF AMERICA— RATHBUN. 



519 



tionally narrower. Orbits shorter and wider in houvieri^ and longer in 

 their outer than their inner half (fig. 9, a) ; in chilensis they are of equal 

 length in their outer and inner half. The maxillipeds are similar to 

 those of chiletisis, except that the merus is wider j its anterior width is 

 about equal to its length measured from 

 the antero- external angle (fig. 9, b), while 

 in chilensis its anterior width is much less 

 than its length. 



Dimensions. — Male: Length, 31.5 mm.; 

 width, 52.3 mm. ; exorbital width, 26.5 mm. 



Types. — Paris Museum, one male and 

 one female; No. 20050, U.S.N.M., one male. 

 United States of Colombia; M. Lindig. 



The specific name is in honor of Prof. E. L. Bouvier, through whose 

 liberality the U. S. National Museum has made many valuable additions 

 to its collection of freshwater crabs. 



Fia. 9.— PSEUDOTHELPHUSA BOUVTEEI, 

 FEMALE, NATCEAL SIZE. CI. FRONT. 



b. Maxilliped. 



Santa Fe de Bogota, 



PSEUDOTHELPHUSA AGASSIZII, new species. 



Superior margin of front tuberculate, not Jceeled, unilobate; surface 

 coarsely granulate; cervical sutures convex to each other ; merus of max- 

 illipeds with outer margin convex ; exognath reduced to a stump. 



Allied to P. refexifrons and P. denticnlata. Carapace convex, nar- 

 rower than in refexifrons or denticulata, very coarsely granulate, espe- 

 cially toward the lateral margins. Cervical suture slightly arched 

 forward. The faintest trace of a median groove; branchio-cardiac lines 

 deep. Lateral margin with about 22 distinct tuberculiform teeth; 

 exorbital tooth larger than any other. Superior frontal margin not 

 bilobed, truncate, rounding upward at the extremities ; edge tubercu- 

 late, not projecting. Inferior bordei sinuous, margined, somewhat 

 four-lobed (fig. 10, a); corners rounding; sides oblique; surface of 

 frout inclined downward and backward. Superior margin of orbit 

 slightly sinuous, sloping backward a little, except toward the outer 



angle. Orbit large, wider than one-half the 

 width of the front; eyes large, not quite filling 

 orbit. Median tooth of epistome very long, 

 produced downward and forward. Maxilli- 

 peds much as in refexifrons, the merus having 

 a thickened and strongly beveled outer margin 

 (fig. 10, b). Abdomen of female narrow, ap- 

 parently mature. 



Chelipeds very unequal, rather stout; sur- 

 face covered with rough, scaly granules. 

 Lower margin of merus bordered by rather large tubercles or blunt 

 spines; upper surface very rough. Carpal spine sharp. Palm (fig. 

 10, c) stout, both margins convex; fingers not gaping, and with broad 

 triangular teeth. Ambulatory legs rough with spinules and spiniform 



Fl(i. 10.— rSEUDOTHELPHUSA 

 AGASSIZII. FEMALE, NATURAL 



SIZE. a. Front, b. Maxil- 

 liped. c Larger chela. 



